Luminous display device

Patent metadata

Field	Value
Publication number	US-10859978-B2
Application number	US-201816052762-A
Country	US
Kind code	B2
Filing date	Aug 2, 2018
Priority date	Aug 21, 2017
Publication date	Dec 8, 2020
Grant date	Dec 8, 2020

Abstract

The present invention concerns a holographic display device incorporated in a timepiece device comprising at least one movable hand, having a light source at its peripheral end, and a watch glass comprising at least one hologram at its periphery, said light source being arranged on the hand so that it reconstructs said hologram when it moves into a predetermined angular sector.

First claim

What is claimed is:

1. A watch, comprising:
a holographic display device comprising a movable hour hand having a first light source mounted at a peripheral end of the hour hand and a movable minute hand having a second light source mounted at a peripheral end of the minute hand; and
a watch glass comprising hour symbol holograms at a first circumference and minute symbol holograms at a second circumference, said first light source being arranged on the hour hand so that it successively reconstructs said hour symbol holograms when the hour hand moves into a first predetermined angular sector of the glass and said second light source being arranged on the minute hand so that it successively reconstructs said minute symbol holograms when the minute hand moves into a second predetermined angular sector of the glass.

2. The display device according to claim 1 , wherein the glass includes at least one diffraction grating, arranged on the an internal surface of the glass to diffract light at an angle greater than the critical angle of total reflection, said hour symbol holograms being disposed on the glass in order to be reconstructed by a diffracted beam from the first light source after total reflection at the external surface of the glass.

3. The display device according to claim 2 , wherein the diffraction grating is a blazed or holographic grating.

4. The display device according to claim 2 , wherein a plurality of diffraction gratings are disposed on third circumference, the second light source at the peripheral end of the minute hand being arranged to successively illuminate, during use, the diffraction gratings of the third circumference, and the diffracted light successively reconstructing the corresponding minute symbol holograms on the second circumference.

5. The device according to claim 4 , wherein the first light source on the hour hand is arranged to illuminate in succession, during use, a plurality of diffraction gratings disposed on a fourth circumference, wherein the diffracted light successively reconstructs the hour symbol holograms disposed on the first circumference.

6. The device according to claim 1 , wherein the first light source and the second light source each include a primary source selected from the group consisting of a light-emitting diode, laser diode and vertical-cavity laser diode.

7. The device according to claim 6 , wherein each of the first light source and the second light source is monochromatic.

8. The device according to claim 1 , wherein the first light source includes a waveguide housed inside the hour hand.

9. The device according to claim 1 , wherein the hour symbol holograms and the minute symbol holograms include a three-dimensional structure, etched, stamped, embossed or moulded on a surface of the glass facing the first light source and the second light source.

Assignees

• Swatch Group Res & Dev Ltd

Inventors

• Tortora Pierpasquale

Classifications

• G04B19/10 Primary

  Ornamental shape of the graduations or the surface of the dial; Attachment of the graduations to the dial {(cases for special purposes, e.g. ring or button watches G04B37/12; indicating means with special effects G04B45/00)} · CPC title

• G04B39/00

  Watch crystals; Fastening or sealing of crystals; Clock glasses · CPC title

• G04B19/226

  three-dimensionally shaped, e.g. terrestrial globes, cylinders and the like · CPC title

• G04B19/305

  the hands carrying the light source (hands and manufacture thereof G04B19/042; projection of hands or dials G04B19/34; illumination of scales and/or hands on moving scales H03J1/02; on compasses G01C17/24; on weighing apparatus G01G23/18; on measuring instruments G01D11/28) · CPC title

• G04B19/30 Primary

  Illumination of dials or hands {(dials in general G04B19/06; moving indicating means with numbers or hands, in general G04B19/20; arrangements for indicating different local apparent times by means of a globe illuminated from inside G04B19/22; continuous indication of the time by non-electric light sources G04B25/00, e.g. by electric lamps G04C17/02; illumination by electric lamps which function at fixed times or periodically G04C19/02; illuminated panels G09F13/00)} · CPC title